4KRBM Roller Kelly Bushings are used for 17 1/2~49 1/2 inch rotary tables.They are designed and manufactured according to API Spec 7K. 


Our company produce the master bushings and insert bowls with the size from 17 1/2 to 37 1/2 inch.They are cast by high~quality alloy steel and the sizes conform to API Spec 7K.There are two types:pin drive and square drive.The rotary slips,drill collar slips,casing slips or roller kelly bushings conforming to API standard can be contained in them.


We also produce casing bushings and master bushing accessories.